There are many known orthotic devices including those specifically directed to rehabilitation of various joints such as elbows, knees, wrists and ankles. Typically, these apparatuses are static or have a single pressure/force that is applied during operation. Those forces may be uneven across the device. Usually, the forces are focused solely on extension or flexion, but not both.
One problem with conventional devices is the inability to easily customize those devices for a particular patient. A given arrangement may be useful and appropriate for one patient, but not as effective for another. Further, those devices may be difficult to adjust between, for instance, flexion or extension. Also, typical devices are not able to easily vary their tension and quantify such for a given patient. For instance, a weak or frail patient may require less tension or force during therapy than a large or strong patient. Also, as a patient gains strength during therapy, the device needs to be able to be variable as the therapy process moves forward.